1. Field of the Invention
The present invention relates to a hinge base provided with adjustment of the position in a vertical direction or in the direction of the hinging axis.
2. State of the Prior Art
Hinges used in the furniture-manufacturing industry are usually provided with a mechanism enabling vertical adjustment of the door so as to allow an optimal alignment with the furniture framework and with other possible adjacent doors.
In the simplest and cheapest form, vertical adjustment is obtained by the same screws fastening the hinge base to the side of the piece of furniture. In accordance with this known technique, the screws for fastening to the piece of furniture, possibly previously mounted on the side flanges of the base, are housed in slots elongated in the direction of the pivot axis of the door. In this way, when the screws are fastened to the side but nut yet fully tightened, vertical sliding of the base and of the hinge, and the door therewith, can be carried out along the stroke allowed by the oval shape of the slots.
This system is surely cheap but it has different drawbacks; since at least two fastening screws are required for each base, at least four screws are to be operated for vertical adjustment of a door; in addition, usually wood screws are utilized and carrying out loosening and tightening operations several times in the same seat may cause an important grip reduction.
Another drawback is represented from a non-continuity in the adjustment; when the screws are loosened, the door falls to the lowest position by effect of its own weight and the correct adjustment position can be only found by attempts.
To prevent the above described drawbacks, the solution generally used in the known art consists in separating fastening from adjustment; for this reason the base is made up of two pieces, a plate directly fastened to the side of the piece of furniture (by means of two wood screws, for example) and a body fastened to the plate by a single metric screw with an oval recess or by a riveted eccentric pin capable of enabling a continuous vertical movement.
The most important technical problem connected with this solution concerns fastening between the plate and the base body that obviously must be as rigid as possible. If fastening takes place by a screw, tightening of which takes place in an oval recess provided at a central position on the base body, the gripping degree can be sufficient, but often the fastening screw, for construction reasons, must be placed laterally on one of the side flanges of the base.
The problem is still more critical if the solution of carrying out fastening by a riveted eccentric pin is adopted. In fact, this solution offers the great advantage of a continuous adjustment, but is not able to ensure the same gripping action as that of a well tightened screw. Many known embodiments of this type of base are known but generally the mechanisms ensuring a good operation have a high manufacturing cost.
It is a general aim of the present invention to obviate the above mentioned drawbacks by providing a position-adjustable base enabling an efficient and continuous adjustment, steady fastening and minimum manufacturing cost.